Colds are infections of the upper whistle tract caused mainly by viral infections. Patients often have symptoms such as nasal discomfort, sneezing, runny nose, fever, cough and headache. There are two types of colds: common cold and influenza. A runny nose during a cold is caused by a virus that invades the body’s throat and binds with airway epithelial cells, causing the body’s own resistance response and producing a large number of protective factors. These beneficial factors, while killing the virus to protect itself, increase the permeability of the blood vessel wall in the nasopharynx, and part of the plasma leaks out into the nasal mucosa, which in turn increases the secretion of the glands in the nasal cavity, resulting in more nasal discharge than usual and uncomfortable symptoms such as runny nose and unventilated nose. In addition, some patients may also experience cough, phlegm, headache, fever and other symptoms. Runny nose is a common symptom of cold. Drinking water regularly and cleaning in time can relieve nasal congestion and other discomforts. If you feel that the symptoms of cold are more serious or accompanied by high fever, it is recommended to go to the hospital promptly to consult the whistling department to avoid aggravation of the condition. In daily life, patients need to pay attention to avoid cold, avoid strain, strengthen physical exercise, improve their own immunity, you can reduce the chances of a cold.